Amyotrophic Lateral Sclerosis (Lou Gehrig Disease) Glossary of TermsThe following are health and medical definitions of terms that appear in the Amyotrophic Lateral Sclerosis (Lou Gehrig Disease) article.
Airway: The path air follows to get into and out of the lungs. The mouth and nose are the normal entry and exit ports. Entering air then passes through the back of the throat (pharynx), continues through the voice box (larynx), down the trachea, and finally out the branching tubes known as bronchi. Anxiety: A feeling of apprehension and fear characterized by physical symptoms such as palpitations, sweating, and feelings of stress. Anxiety disorders are serious medical illnesses that affect approximately 19 million American adults. These disorders fill people's lives with overwhelming anxiety and fear. Unlike the relatively mild, brief anxiety caused by a stressful event such as a business presentation or a first date, anxiety disorders are chronic, relentless, and can grow progressively worse if not treated. Aspiration: Removal of a sample of fluid and cells through a needle. Aspiration also refers to the accidental sucking in of food particles or fluids into the lungs. Atrophy: Wasting away or diminution. Muscle atrophy is wasting of muscle, decrease in muscle mass. Autoimmune: Pertaining to autoimmunity, a misdirected immune response that occurs when the immune system goes awry and attacks the body itself. Biopsy: The removal of a sample of tissue for purposes of diagnosis. (Many definitions of "biopsy" stipulate that the sample of tissue is removed for examination under a microscope. This may or may not be the case. The diagnosis may be achieved by other means such as by analysis of chromosomes or genes.) Bladder: Any pouch or other flexible enclosure that can hold liquids or gases but usually refers to the hollow organ in the lower abdomen that stores urine -- the urinary bladder. The kidneys filter waste from the blood and produce urine, which enters the bladder through two tubes called ureters. Urine leaves the bladder through another tube, the urethra. In women, the urethra is a short tube that opens just in front of the vagina. In men, it is longer, passing through the prostate gland and then the penis. Infection of the bladder is called cystitis. Bowel: Another name for the intestine. The small bowel and the large bowel are the small intestine and large intestine, respectively. Brain: That part of the central nervous system that is located within the cranium (skull). The brain functions as the primary receiver, organizer and distributor of information for the body. It has two (right and left) halves called "hemispheres." Breathing: The process of respiration, during which air is inhaled into the lungs through the mouth or nose due to muscle contraction, and then exhaled due to muscle relaxation. Chest: The area of the body located between the neck and the abdomen. The chest contains the lungs, the heart and part of the aorta. The walls of the chest are supported by the dorsal vertebrae, the ribs, and the sternum. Cognitive: Pertaining to cognition, the process of knowing and, more precisely, the process of being aware, knowing, thinking, learning and judging. The study of cognition touches on the fields of psychology, linguistics, computer science, neuroscience, mathematics, ethology and philosophy. Constipation: Infrequent (and frequently incomplete) bowel movements. The opposite of diarrhea, constipation is commonly caused by irritable bowel syndrome, diverticulosis, and medications (constipation can paradoxically be caused by overuse of laxatives). Colon cancer can narrow the colon and thereby cause constipation. The large bowel (colon) can be visualized by barium enema x-rays, sigmoidoscopy, and colonoscopy. Barring a condition such as cancer, high-fiber diets can frequently relieve the constipation. Cure: 1. To heal, to make well, to restore to good health. Cures are easy to claim and, all too often, difficult to confirm. Dementia: Significant loss of intellectual abilities such as memory capacity, severe enough to interfere with social or occupational functioning. Depression: An illness that involves the body, mood, and thoughts, that affects the way a person eats and sleeps, the way one feels about oneself, and the way one thinks about things. A depressive disorder is not the same as a passing blue mood. It is not a sign of personal weakness or a condition that can be wished away. People with a depressive disease cannot merely "pull themselves together" and get better. Without treatment, symptoms can last for weeks, months, or years. Appropriate treatment, however, can help most people with depression. Diagnosis: 1 The nature of a disease; the identification of an illness. 2 A conclusion or decision reached by diagnosis. The diagnosis is rabies. 3 The identification of any problem. The diagnosis was a plugged IV. Diarrhea: A familiar phenomenon with unusually frequent or unusually liquid bowel movements, excessive watery evacuations of fecal material. The opposite of constipation. The word "diarrhea" with its odd spelling is a near steal from the Greek "diarrhoia" meaning "a flowing through." Plato and Aristotle may have had diarrhoia while today we have diarrhea. There are myriad infectious and noninfectious causes of diarrhea. Dizziness: Painless head discomfort with many possible causes including disturbances of vision, the brain, balance (vestibular) system of the inner ear, and gastrointestinal system. Dizziness is a medically indistinct term which laypersons use to describe a variety of conditions ranging from lightheadedness, unsteadiness to vertigo. Dysarthria: Speech that is characteristically slurred, slow, and difficult to produce (difficult to understand). The person with dysarthria may also have problems controlling the pitch, loudness, rhythm, and voice qualities of their speech. Dysfunction: Difficult function or abnormal function. Dysphagia: Difficulty in swallowing, swallowing problems. Dysphagia is due to problems in nerve or muscle control. It is common, for example, after a stroke. Dysphagia compromises nutrition and hydration and may lead to aspiration pneumonia and dehydration. Electrophysiologic: Pertaining to electrophysiology. Familial: A condition that is tends to occur more often in family members than expected by chance alone. A familial disease may be genetic (such as cystic fibrosis) or environmental (such as tuberculosis). Familial ALS: ALS (amyotrophic lateral sclerosis) in which there a family history of the disease. Familial ALS constitutes 5 to 10% of all cases of ALS. There are a number of different types of familial ALS. Frontal: In anatomy, pertaining to the forehead. As, for example, the frontal bone, frontal sinus, and frontal nerve. From the Latin "frons" meaning the forehead or brow. Frontal lobe: The part of each hemisphere of the brain located behind the forehead that serves to regulate and mediate the higher intellectual functions. The frontal lobes have intricate connections to other areas of the brain. In the frontal lobes, we meld emotions, cognition, error detection, volition, a sense of self, and more to create our social brain. Gene: The basic biological unit of heredity. A segment of deoxyribonucleic acid (DNA) needed to contribute to a function. Glutamate: A form of glutamic acid. See: Glutamic acid. Involuntary: Done other than in accordance with the conscious will of the individual. The opposite of voluntary. Juvenile: Between infantile and adult as, for example, in juvenile rheumatoid arthritis (onset before age 16 years) and juvenile diabetes (type 1 diabetes). Lab test: A test that is done in the laboratory where the appropriate equipment, supplies, and certified expertise are available. Lateral: 1. In anatomy, the side of the body or a body part that is farther from the middle or center of the body. Typically, lateral refers to the outer side of the body part, but it is also used to refer to the side of a body part. For example, when referring to the knee, lateral refers to the side of the knee farthest from the opposite knee. The opposite of lateral is medial. Liver: An organ in the upper abdomen that aids in digestion and removes waste products and worn-out cells from the blood. The liver is the largest solid organ in the body. The liver weighs about three and a half pounds (1.6 kilograms). It measures about 8 inches (20 cm) horizontally (across) and 6.5 inches (17 cm) vertically (down) and is 4.5 inches (12 cm) thick. See the entire definition of Liver Lobe: Part of an organ that appears to be separate in some way from the rest. A lobe may be demarcated from the rest of the organ by a fissure (crack), sulcus (groove), connective tissue or simply by its shape. For example, there are the frontal, parietal, temporal, and occipital lobes of the brain. Lungs: The lungs are a pair of breathing organs located with the chest which remove carbon dioxide from and bring oxygen to the blood. There is a right and left lung. Memory: 1. The ability to recover information about past events or knowledge. 2. The process of recovering information about past events or knowledge. 3. Cognitive reconstruction. The brain engages in a remarkable reshuffling process in an attempt to extract what is general and what is particular about each passing moment. Metabolic: Relating to metabolism, the whole range of biochemical processes that occur within us (or any living organism). Metabolism consists of anabolism (the buildup of substances) and catabolism (the breakdown of substances). Microscope: An optical instrument that augments the power of the eye to see small objects. The name microscope was coined by Johannes Faber (1574-1629) who in 1628 borrowed from the Greek to combined micro-, small with skopein, to view. Although the first microscopes were simple microscopes, most (if not all) optical microscopes today are compound microscopes. Motor: In medicine, having to do with the movement of a part of the body. Something that produces motion or refers to motion. For example, a motor neuron is a nerve cell that conveys an impulse to a muscle causing it to contract. The term "motor" today is also applied to a nerve that signals a gland to secrete. Motor is as opposed to sensory. Motor neuron: A neuron that sends electrical output signals to muscle neurons. Also called a motoneuron. Motor neuron disease: A group of neurological diseases characterized by steadily progressive deterioration of the motor neurons in the brain, brainstem and spinal cord that send instructions in the form of electrical impulses to the muscles, leading to muscle weakness and wasting. MRI: Abbreviation and nickname for magnetic resonance imaging. For more information, see: Magnetic Resonance Imaging; Paul C. Lauterbur; Peter Mansfield. Mucus: A thick slippery fluid produced by the membranes lining certain organs such as the nose, mouth, throat, and vagina. Mucus is the Latin word for "a semifluid, slimy discharge from the nose." Note that mucus is a noun while the adjective is mucous. Muscle: Muscle is the tissue of the body which primarily functions as a source of power. There are three types of muscle in the body. Muscle which is responsible for moving extremities and external areas of the body is called "skeletal muscle." Heart muscle is called "cardiac muscle." Muscle that is in the walls of arteries and bowel is called "smooth muscle." Muscle biopsy: A minor surgical procedure done under local anesthetic using a needle or a small incision to remove a small sample of muscle. The procedure may be done to confirm a clinical diagnosis, distinguish between nerve and muscle disorders, identify a metabolic defect of muscle, diagnose diseases of connective tissue and blood vessels, detect muscle inflammation, or rule out muscle disease. Afterwards, there may be minor discomfort and bruising at the biopsy site which usually takes a week to heal fully. Muscular: Having to do with the muscles. Also, endowed with above average muscle development. Muscular system refers to all of the muscles of the body collectively. Muscular dystrophy: One of a group of genetic diseases characterized by progressive weakness and degeneration of the skeletal or voluntary muscles which control movement. The muscles of the heart and some other involuntary muscles are also affected in some forms of muscular dystrophy, and a few forms involve other organs as well. Mutation: A permanent change, a structural alteration, in the DNA or RNA. In humans and many other organisms, mutations occur in DNA. However, in retroviruses like HIV, mutations occur in RNA which is the genetic material of retroviruses. Nausea: Nausea, is the urge to vomit. It can be brought by many causes including, systemic illnesses, such as influenza, medications, pain, and inner ear disease. When nausea and/or vomiting are persistent, or when they are accompanied by other severe symptoms such as abdominal pain, jaundice, fever, or bleeding, a physician should be consulted. Neck: The part of the body joining the head to the shoulders. Also, any narrow or constricted part of a bone or organ that joins its parts as, for example, the neck of the femur bone. Nerve: A bundle of fibers that uses chemical and electrical signals to transmit sensory and motor information from one body part to another. See: Nervous system. Neurological: Having to do with the nerves or the nervous system. Neurologist: A doctor who specializes in the diagnosis and treatment of disorders of the nervous system. Neurology: The medical specialty concerned with the diagnosis and treatment of disorders of the nervous system -- the brain, the spinal cord, and the nerves. Neuron: A nerve cell that sends and receives electrical signals over long distances within the body. A neuron may send electrical output signals to muscle neurons (called motor neurons or motoneurons) and to other neurons. A neuron may receive electrical input signals from sensory cells (called sensory neurons) and from other neurons. A neuron that simply signals another neuron is called an interneuron. Neurotransmitter: A chemical that is released from a nerve cell which thereby transmits an impulse from a nerve cell to another nerve, muscle, organ, or other tissue. A neurotransmitter is a messenger of neurologic information from one cell to another. Neutrophil: A type of white blood cell, specifically a form of granulocyte, filled with neutrally-staining granules, tiny sacs of enzymes that help the cell to kill and digest microorganisms it has engulfed by phagocytosis. The mature neutrophil has a segmented nucleus (it is called a seg or poly) while the immature neutrophil has band-shape nucleus (it is called a band). The neutrophil has a lifespan of about 3 days. Nutrition: 1) The science or practice of taking in and utilizing foods. 2) A nourishing substance, such as nutritional solutions delivered to hospitalized patients via an IV or IG tube. Nutritionist: 1) In a hospital or nursing home, a person who plans and/or formulates special meals for patients. It can also simply be a euphemism for a cook who works in a medical facility but who does not have extensive training in special nutritional needs. 2) In clinical practice, a specialist in nutrition. Nutritionists can help patients with special needs, allergies, health problems, or a desire for increased energy or weight change devise healthy diets. Some nutritionists in private practice are well- trained, hold a degree and are licensed. Depending on state law, however, a person using the title may not be trained or licensed at all. Onset: In medicine, the first appearance of the signs or symptoms of an illness as, for example, the onset of rheumatoid arthritis. There is always an onset to a disease but never to the return to good health. The default setting is good health. Pain: An unpleasant sensation that can range from mild, localized discomfort to agony. Pain has both physical and emotional components. The physical part of pain results from nerve stimulation. Pain may be contained to a discrete area, as in an injury, or it can be more diffuse, as in disorders like fibromyalgia. Pain is mediated by specific nerve fibers that carry the pain impulses to the brain where their conscious appreciation may be modified by many factors. Paralysis: Loss of voluntary movement (motor function). Paralysis that affects only one muscle or limb is partial paralysis, also known as palsy; paralysis of all muscles is total paralysis, as may occur in cases of botulism. Pathologist: A doctor who identifies diseases by studying cells and tissues under a microscope. Percutaneous: Through the skin, as in a percutaneous biopsy. Pharmacy: A location where prescription drugs are sold. A pharmacy is, by law, constantly supervised by a licensed pharmacist. Physical therapy: A branch of rehabilitative health that uses specially designed exercises and equipment to help patients regain or improve their physical abilities. Physical therapists work with many types of patients, from infants born with musculoskeletal birth defects, to adults suffering from sciatica or the after- effects of injury, to elderly post-stroke patients. Pneumonia: Inflammation of one or both lungs with consolidation. Pneumonia is frequently but not always due to infection. The infection may be bacterial, viral, fungal or parasitic. Symptoms may include fever, chills, cough with sputum production, chest pain, and shortness of breath. Primary care: The "medical home" for a patient, ideally providing continuity and integration of health care. All family physicians and most pediatricians and internists are in primary care. The aims of primary care are to provide the patient with a broad spectrum of care, both preventive and curative, over a period of time and to coordinate all of the care the patient receives. Primary care provider: In insurance parlance, a physician chosen by or assigned to a patient, who both provides primary care and acts as a gatekeeper to control access to other medical services. Progressive: Increasing in scope or severity. Advancing. Going forward. In medicine, a disease that is progressive is going from bad to worse. Public health: The approach to medicine that is concerned with the health of the community as a whole. Public health is community health. It has been said that: "Health care is vital to all of us some of the time, but public health is vital to all of us all of the time." Quality of life: An important consideration in medical care, quality of life refers to the patient's ability to enjoy normal life activities. Some medical treatments can seriously impair quality of life without providing appreciable benefit, while others greatly enhance quality of life. Reflex: A reaction that is involuntary. The corneal reflex is the blink that occurs with irritation of the eye. The nasal reflex is a sneeze. Regimen: With the accent on the first syllable (reg as in Reggie Jackson), a regimen is a plan, a regulated course such as a diet, exercise or treatment, designed to give a good result. A low-salt diet is a regimen. Respiratory: Having to do with respiration, the exchange of oxygen and carbon dioxide. From the Latin re- (again) + spirare (to breathe) = to breathe again. Respiratory failure: Inability of the lungs to perform their basic task of gas exchange, the transfer of oxygen from inhaled air into the blood and the transfer of carbon dioxide from the blood into exhaled air. The basis of respiratory failure may be failure of the exchange of oxygen and carbon dioxide within the tiny air sacs (alveoli) in the lungs; failure of the muscles required to expand the lungs; or failure of the brain centers controlling respiration. Respiratory therapist: A person who has graduated from an approved respiratory therapist program and is qualified to provide respiratory care under the supervision of a physician. In the US, respiratory therapists may be is registered by the National Board for Respiratory Care. Risk factor: Something that increases a person's chances of developing a disease. Rule out: A term much used in medicine, meaning to eliminate or exclude something from consideration. The ACB (albumin cobalt binding) test helps rule out a heart attack in the differential diagnosis of severe chest pain. Saliva: a watery secretion in the mouth produced by the salivary glands that aids in the digestion of food. Saliva also serves to moisten and cleanse the mouth, including the tongue and teeth, and contains substances that can play a role in the prevention of infection. Saliva aids digestion by moistening food and contains enzymes that begin the digestion process. Also known as spit. Sclerosis: Localized hardening of skin. Sequencing: Learning the order of nucleotides (base sequences) in a DNA or RNA molecule or the order of amino acids in a protein. Sleep: The body's rest cycle. Spasticity: A state of increased tone of a muscle (and an increase in the deep tendon reflexes). For example, with spasticity of the legs (spastic paraplegia) there is an increase in tone of the leg muscles so they feel tight and rigid and the knee jerk reflex is exaggerated. Speech therapy: The treatment of speech and communication disorders. The approach used depends on the disorder. It may include physical exercises to strengthen the muscles used in speech (oral-motor work), speech drills to improve clarity, or sound production practice to improve articulation. Spinal cord: The major column of nerve tissue that is connected to the brain and lies within the vertebral canal and from which the spinal nerves emerge. Thirty-one pairs of spinal nerves originate in the spinal cord: 8 cervical, 12 thoracic, 5 lumbar, 5 sacral, and 1 coccygeal. The spinal cord and the brain constitute the central nervous system (CNS). The spinal cord consists of nerve fibers that transmit impulses to and from the brain. Like the brain, the spinal cord is covered by three connective-tissue envelopes called the meninges. The space between the outer and middle envelopes is filled with cerebrospinal fluid (CSF), a clear colorless fluid that cushions the spinal cord against jarring shock. Also known simply as the cord. Sporadic: Occurring upon occasion or in a scattered, isolated or seemingly random way. Stomach: 1. The sac-shaped digestive organ that is located in the upper abdomen, under the ribs. The upper part of the stomach connects to the esophagus, and the lower part leads into the small intestine. Stress: Forces from the outside world impinging on the individual. Stress is a normal part of life that can help us learn and grow. Conversely, stress can cause us significant problems. Stroke: The sudden death of some brain cells due to a lack of oxygen when the blood flow to the brain is impaired by blockage or rupture of an artery to the brain. A stroke is also called a cerebrovascular accident or, for short, a CVA. Substance: 1. Material with particular features, as a pressor substance. Surgeon: A physician who treats disease, injury, or deformity by operative or manual methods. A medical doctor specialized in the removal of organs, masses and tumors and in doing other procedures using a knife (scalpel). The definition of a "surgeon" has begun to blur in recent years as surgeons have begun to minimize the cutting, employ new technologies that are "minimally invasive," use scopes, etc. Surgery: The word "surgery" has multiple meanings. It is the branch of medicine concerned with diseases and conditions which require or are amenable to operative procedures. Surgery is the work done by a surgeon. By analogy, the work of an editor wielding his pen as a scalpel is s form of surgery. A surgery in England (and some other countries) is a physician's or dentist's office. Therapeutics: In medicine, the branch that deals specifically with the treatment of disease and the art and science of healing. Therapy: The treatment of disease. Tiredness: See: Tired. Tongue: The tongue is a strong muscle anchored to the floor of the mouth. It is covered by the lingual membrane which has special areas to detect tastes. Trachea: A tube-like portion of the breathing or "respiratory" tract that connects the "voice box" (larynx) with the bronchial parts of the lungs. See the entire definition of Trachea Tracheostomy: A surgical operation to create an opening (stoma) into the windpipe (the trachea). The opening itself can also be called a tracheostomy. Trauma: Any injury, whether physically or emotionally inflicted. "Trauma" has both a medical and a psychiatric definition. Medically, "trauma" refers to a serious or critical bodily injury, wound, or shock. This definition is often associated with trauma medicine practiced in emergency rooms and represents a popular view of the term. In psychiatry, "trauma" has assumed a different meaning and refers to an experience that is emotionally painful, distressful, or shocking, which often results in lasting mental and physical effects. Twitch: an involuntary contraction of a group of muscles, also known as a fasciculation. Twitching: Involuntary contractions of groups of muscle fibers. Also known as fasciculations. Fasciculations can occur in normal individuals without an associated disease or condition and can also occur as a result of illness, such as muscle cramps, nerve diseases, and metabolism imbalances. Ventilator: A ventilator is a machine which mechanically assists patients in the exchange of oxygen and carbon dioxide (sometimes referred to as artificial respiration). Voluntary: Done in accordance with the conscious will of the individual. The opposite of involuntary. |
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Amyotrophic Lateral Sclerosis (Lou Gehrig Disease)
Dementia in Amyotrophic Lateral Sclerosis (Lou Gehrig Disease) »
Dementia in ALS Overview
Amyotrophic lateral sclerosis (ALS) is a devastating disorder. It affects the part of the nervous system that controls voluntary movements. ALS is sometimes called Lou Gehrig's disease, after the famous baseball player who died of the disease. The muscles become progressively weaker, and the disease eventually leads to paralysis and death.
ALS is one of a group of diseases known as motor neuron diseases. Neurons are nerve cells, and motor neurons control movement. Persons with motor neuron disease gradually lose muscle control and become paralyzed. No cure is available for ALS or any other motor neuron disease. The effects of these diseases are not reversible. Most people with ALS die within 5 years of the onset of symptoms.
Most experts believe that ALS does not affect a person’s mental processes. In most people, neither cognitive processes (such as thinking, learning, memory, and speech) nor behavior is affected. O...
Read the Dementia in Amyotrophic Lateral Sclerosis (Lou Gehrig Disease) article »
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